1. FIELD OF THE INVENTION
The present invention relates to an optical system for information processing, and more particularly to an optical system for modulating each of a plurality of laser beams independently and for recording information on different areas of a recording material optically and simultaneously by means of the modulated laser beams.
2. DESCRIPTION OF THE PRIOR ART
When it is desired to effect laser recording on different recording materials independently and simultaneously, there has been employed, for example, a laser printer system such as shown in FIG. 1 of the accompanying drawings, in which a pair of laser beams 1 and 2 are light-modulated independently for effecting laser recording on different areas of a recording material 9. Referring to FIG. 1, each of rotating polygonal mirrors 3 and 4 is used to deflect the laser beam 1 or 2 for effecting scanning with the laser beams. Further, each of lenses 5 and 6 is the so-called F-.theta. lens and is used to convert each laser beam into a fine scanning spot on the recording material 9. The recording material is moved in the direction indicated by arrows, and therefore the laser recording can be effected all over the surface of the recording material 9.
In such an optical system for laser printer as shown in FIG. 1, however, both the number of rotating polygonal mirrors and the number of F-.theta. lenses are required to be equal to the number of independent laser recording. Accordingly, the optical system shown in FIG. 1 is large in size, complicated in structure, and expensive.